I've been getting some wrist pain on my right that I think is due to my mousing position. It's mostly present at the crease of the wrist, and doesn't come with any tingling sensations or numbness. I was thinking of moving to a more upright mouse. From a glance at the options, it seems like the MS natural 6000 and evoluent would be best at moving my hand more upright without putting any extra strain on my thumb (which i've had problems with before).

Does anyone have any experience with these two side by side? I can get some kind of discount on the MS mouse, but it looks quite a bit less extreme than the evoluent. Thoughts?